Aryl-Δ2-pyrazoline als optische Aufhellungsmittel

Abstract

In eine Suspension von 10:5 g (0,05 Mol) 1-Methdnsulfonyl-3-n-butylthioharnstoff in 65 in1 Chlorbenzol werden 5 g (0,05 Mot) Phosgen in 40 ml Chlorbenzol tropfenweise bei 5 "C eingetragen. Nach einstundigem Ruhren bei Zimmertemperatur erhitzt man zum Sieden und entfernt das iiicht umgesetzte Phosgen mit Stickstoff. Durch Abdestillieren des LLisungsmittels und Vakuumdestillation des Riickstandes gewinnt man 7,O g (79,5 %) Methansulfonyl-n-butylcarbodiimid, K p = 103-105°C/0,3 Torr; nk435 = 1,4798 (vgl. Abschnitt IV, 2). In eine Suspension von 8,5 g (0,023 Mol) 1-p-Toluolsulfonyl-3-phenylthiol1arnstoff in 50 ml Chlorbenzol wird tropfenweise eine Losung von 2,8 g (0,028 Mol) Phosgen in 35 nil Chlorbenzol eingetragen. Nach einstundigem Ruhren wird das Losungsmittel im Vakuum abdestilliert. Aus dem Ruckstand, 9 g (97,3 %), Fp = 128-131 "C, kann analysenreines 3-Phenyl-4-p-toluolsulfonylimino-l,3-thiazetidin-2-on, F p = 137 bis 139 "C, durch Umkristallisation aus Athylacetat erhalten werden (vgl. Abschn. IV, 2). 17. 2-Phenylimino

Organic scintillators with unusually large Stokes' shifts

“…The methyl and methoxy substituted 1,3-diphenyl-2-pyrazolines were prepared by standard procedures. 4 The condensation of the appropriately substituted Mannich bases with phenylhydrazine or the appropriately substituted phenylhydrazine gave methyl and/or methoxy substituted 1,3-diphenyl-2-pyrazolines with yields of 55 to 90%. l-Phenyl-3-mesityl-2-pyrazoline and l-phenyl-3-(2/,4,,6'-trimethoxyphenyl)-2-pyrazoline were synthesized by condensation of mesityl vinyl ketone and 2,4,6-trimethoxyphenyl vinyl ketone with phenylhydrazine, respectively.…”

Ketone Derivatives of Propargylamines as Synthetic Equivalents of Conjugated 2,4,1-Enynones in the Synthesis of Acetylenic 2-Pyrazolines and Pyrazoles

“…Therefore, we have observed their absorption and emission spectra in the visible and ultraviolet regions of the light spectrum. Spectral-luminescent characteristics of 2-pyrazolines 5 and 1,3,5-triphenyl-4,5-dihydro-1 H -pyrazoline 8 , are quite similar: each of them has the maximum absorbance in the long-wavelength range λ max 345–358 nm, emission band at 453–464 nm, and an extremely large Stokes shift (ν ss ) that reaches about 91,000 cm –1 correspondingly (see the Experimental Section). In addition to those mentioned above, the luminous intensity increases rather significantly in the order [illustrated with the luminous intensity for compound 5f (%)]: 5d (18) < 5c (45) < 5a (57) < 5b (64) < 5e (92) < 8 (95) < 5f (100); in the case of 2-pyrazolines 5a , c – f , it appears practically in the order of increasing of the substituents’ electron acceptor abilities in Ar 2 .…”

“…In addition to those mentioned above, the luminous intensity increases rather significantly in the order [illustrated with the luminous intensity for compound 5f (%)]: 5d (18) < 5c (45) < 5a (57) < 5b (64) < 5e (92) < 8 (95) < 5f (100); in the case of 2-pyrazolines 5a , c – f , it appears practically in the order of increasing of the substituents’ electron acceptor abilities in Ar 2 . Interestingly, the opposite is true for the set of 3-aryl-1,5-diphenyl-4,5-dihydro-1 H -pyrazoles …”

“…Arylhydrazines 4b – e were obtained by reduction of the corresponding aryl diazonium salts with Na 2 SO 3 and recrystallized from petroleum ether before further procedures. Pyrazoline 8 was obtained according to a known procedure; its characteristics are identical to previously mentioned compounds in the data literature. , …”

Synthesis, characterization, and reactions of selected multichalcone derivatives

“…Pyrazoles are used as ultraviolet stabilizer, anticancer, muscle relaxant, anti‐inflammatory, antipyretic, antiarrhythmic, tranquilizing, anticonvulsant, hypotensive, monoamino oxidase inhibitor, antidiabetic and antibacterial agent [18–23]. Pyrazolines are used to produce photoconductive polymers [24], also used as scintillation solutes [25], as cytotoxic agent [26], they have also broad biological activities; such as psychoanaleptic, anticonvulsant, and antidepressant [27]. Thiazol derivatives have been reported to possess tuberculostatic, antibacterial, and antifungal activities [28].…”